A practical guide to quality
Anyone who is interested in choosing a suitable product containing the key omega-3 fatty acids - eicosapentaenoic (EPA) and docosahexaenoic (DHA) - should be interested in the indicators that help distinguish between a formally acceptable product and a truly high-quality food supplement.
In practice, the following challenges are usually addressed:
1. Amount of active ingredients.
In the vast majority of cases, it's the content EPA and DHA, exceptionally the manufacturer also mentions docosapentaenoic acid (DPA). In quality concentrates, these omega-3s make up approximately 60% or more of the oil by volume. This means that one 1000 mg capsule can contain over 600 mg of the EPA+DHA combination, cheaper products contain a significantly lower concentration of active substances.
It is therefore important read labels and monitor the actual EPA and DHA content per dose.
2. Purity of the product.
Specifically, the risk of contamination by heavy metals and organic chemicals is addressed. In the case of dietary supplements, it is the legal obligation of the manufacturer to ensure that the product does not exceed the permitted limits of contaminants. However, this does not mean that every batch is automatically tested or that the test results are available to the consumer. State supervision is rather random and focuses on meeting the safety minimum. Reputable manufacturers therefore go beyond legal requirements, purposefully purify oils containing omega-3 from heavy metals and organic pollutants, and test each batch in independent laboratories. In doing so, they provide the consumer with the assurance that the product is not only "legally OK", but actually controlled for purity and quality.
It therefore makes sense to look for products that can be independently tested for the purity of individual batches.
3. Oxidative stability of the oil.
Omega-3 fatty acids are very easily and quickly oxidized by oxygen, light and heat, which leads to peroxides and oil rancidity. The O3 source affected in this way not only loses its effectiveness, but is also a health risk (it has a pro-inflammatory effect in the body).
Quality manufacturers therefore process the oil carefully:
- minimize contact with air,
- protects it from heat and light,
- just to be sure, they add antioxidants as protection.
They also consistently monitor the oxidative stability of the oil according to the recommendations of the professional organization GOED (Global Organization for EPA and DHA Omega-3), which sets internationally recognized limits for evaluation freshness and stability of omega-3 oils.
In practice, the following parameters are evaluated in particular:
- Peroxide number (PV) - serves as an indicator of the early stage of oxidation and indicates whether the oil is fresh.
- Anisidine number (AV) - captures the later decomposition products that are responsible for the rancid taste and smell.
- TOTOX (Total Oxidation Value) - combines both values and provides an overall picture of oil quality.
Low values (peroxide number does not exceed 5 meq/kg, anisidine number remains below 20 and TOTOX value is lower than 26) mean a stable, low-oxidized, high-quality omega-3 supplement.
4. Antioxidant content.
To protect against oxidation, manufacturers add antioxidants to fish oils:
It is most often used vitamin E, which is soluble in fats and can trap free radicals in oil.
Its effectiveness depends on:
- Dose.
In low concentrations, it works very effectively, but in high amounts it can have a pro-oxidative effect. Therefore, it is used in doses that provide antioxidant protection without impairing the oxidative stability of the oil itself.
- Form.
There is a difference in effect between isolated alpha-tocopherol and natural mixture of tocopherols and tocotrienols, which together represent a complex of vitamin E. The mixture provides a synergistic effect broader antioxidant protection (individual forms complement and stabilize each other), whereas isolated alpha-tocopherol can disturb the balance of antioxidants in the oil at higher doses.
Another important substance is astaxanthin:
It is a carotenoid with strong antioxidant effects that occurs naturally in seaweed and accumulates in the food chain, for example in krill and salmon, where it contributes to increasing the oxidative stability of lipids. Compared to vitamin E, astaxanthin is more expensive, but its strong antioxidant effect allows effective use in low concentrations.
They are a specific group of antioxidants polyphenols:
Omega-3 oils are most often added in the form of plant extracts, typically from rosemary or from olive leaves. He is an important representative hydroxytyrosol, a powerful polyphenol from olives that has been proven to increase the oxidative stability of oils.
Polyphenols are often used in combination with other antioxidants, where they contribute to the maintenance of omega-3 quality during storage.
The antioxidants used and their form are therefore important indicators of the quality of the omega-3 supplement, as they determine how well the oil is protected against oxidation during storage and use. It is important to emphasize, however, that no antioxidant can completely prevent oxidation if the oil is stored poorly or has already expired. It is therefore necessary to store this group of supplements properly, preferably in a cool and dark place and ideally in the refrigerator after opening.
Part of the process of choosing the right product is deciding which type of omega-3 supplement we prefer. The options are as follows:
Fish oil.
The most widely used type of omega-3 supplement. It is made from fish fat (most often sardines or anchovies) or fish liver (commonly from cod). Fish oil always contains both EPA and DHA in the natural form of triacylglycerols, normally containing around 18% EPA and 12% DHA, corresponding to the natural concentration in fish oil. But there are also concentrated fish oils, where the proportion of omega-3 reaches 50 - 70%. This state is achieved by so-called molecular distillation, during which fatty acids are temporarily converted to ethyl esters, concentrated, and then converted back into re-esterified triglycerides. An advantage triglycerides form (natural or re-esterified) is different better absorption compared to the form of ethyl esters. In contrast ethyl esters omega-3 are more difficult to absorb, especially on an empty stomach, it is necessary to take them with food containing them fat to be absorbed. Therefore, most high-quality supplements today use the triglyceride form (or free fatty acids), while ethyl esters appear mainly in some medicinal preparations and in products that are primarily price-oriented.
Listing the form of omega-3 is a sign of the producer's transparency and helps the consumer estimate the bioavailability and quality of the raw material used.
Krill oil.
Derived from Antarctic krill (tiny crustaceans), it has a naturally reddish color due to its astaxanthin content. Omega-3 in this source is partially bound in triglycerides and largely in phospholipids (lipids forming krill cell membranes). This makes krill oil very good absorbability. In practice, therefore, even a smaller dose of such a supplement can increase the level of EPA/DHA in the blood, similar to a higher dose of fish oil. The disadvantage is the opposite lower concentration EPA and DHA (500 mg of krill oil contains approximately 60 mg of EPA and 30 mg of DHA, while 500 mg of concentrated fish oil can contain as much as 300-400 mg of EPA+DHA). Krill oil is therefore more suitable for those who prefer smaller capsules and do not mind the higher price per omega-3 unit. On the contrary, its advantage is the presence of astaxanthin and the phospholipid form of omega-3 (important for the structure and function of the cell membranes of the nervous system).
Seaweed Oil.
It is produced by controlled cultivation of microalgae (Schizochytrium), which naturally produce omega-3 (interestingly, the main source of EPA and DHA in the food chain is microalgae, fish - with few exceptions - do not produce them, but only accumulate them). This resource contains significantly higher representation DHA, therefore it is often recommended pregnant to women who do not eat fish for fetal development. The downside is a higher price per gram of omega-3 and usually a slightly lower EPA content.
In terms of quality and purity, however, these plant sources definitely do not compete with fish - algae are grown in closed tanks, so the resulting oil does not contain heavy metals or other contaminants from the ocean.
Only when all these factors are taken into account - from the content and form of EPA and DHA, through purity and oxidative stability to the use of suitable antioxidants and the source of the raw material - can we talk about an omega-3 supplement that has a real potential to bring the expected health benefits.
